Copper power green is a solution of copper, nickel and zinc complexes designed for the treatment of itch, fungus and external parasites in freshwater aquariums. Copper, nickel and zinc are, by themselves, extremely toxic to fish and are therefore, not practical for application in aquariums. Copper power green has a unique chelating agent that has the ability to de-toxify the metals as far as fish are concerned but the metallic solution remains toxic towards disease producing organisms.